This chapter explores an unexamined assumption many people have. The assumption is important in many philosophical discussions (e.g. discussions about the hard problem of consciousness). 

When I tell friends that some things will always be impossible (or impossible in principle), their first response is usually something like the following:


“Many things we thought were impossible are now possible. We thought it was impossible to fly to the moon, but now we can. Nothing is really impossible. To think otherwise is to lack humility.”


However, I think some things are always impossible. Impossible means something is impossible at some point(s) in time. Always impossible (or impossible in principle) means something is impossible at all points in time. The point of disagreement is whether we can know if anything is always impossible.

At one time, flying to the moon was impossible, but now it is possible. So, flying to the moon is not always impossible. Some people have argued that the subjectivity, intentionality, and privacy of consciousness will always be impossible to explain using science, math, or logic. But how can they say this if we are never justified in claiming something is always impossible?

In short, it is important to consider the rationality of believing some things are always impossible because many philosophical debates depend on it.



Are any of the following claims always impossible? Discuss/Explain.


  1. In the future, I will meet a married bachelor (assume the words married and bachelor will have the same meaning in the future).
  2. In the future, it may be possible to round the square or find a triangle with 18 sides.
  3. It may be possible for me to both exist and not exist at this exact time and space.
  4. In the future, I may be able to visualize an object outside of space (notice the visualization presupposes space).
  5. In the future, I will use this hammer to produce a beam of light and enlighten my path.
  6. In the future, science will fully explain the subjectivity of consciousness.
  7. In the future, I will eat 4,000 hot dogs in 20 seconds.



Some of these statements seem impossible in principle, though there are different reasons for why they seem impossible in principle. Statements 3 and 6 are the most controversial.


Application and Value

We know some things are always impossible because their starting points (or methodologies) cannot handle the qualitatively different nature of the problems they are addressing. For example, the fourth claim is always impossible because visualization presupposes space, so I will never be able to visualize an object outside of space. I could visualize the effects of an extra dimensional world on a three dimensional world, but I could never visualize an actual nonspatial or extradimensional world.

One of the deepest ideas to think about is the importance of the methodology or tools we use. These methods and tools are like the lenses through which we view the world, and very few people take the time to think about the lenses themselves. Most people assume that what they see through the lenses is reality.

What are these lenses? They are introspection, science, math, logic, past experience, and so on. None of the lenses have a monopoly on knowledge.

One genius who explored this theme in depth is Immanuel Kant. Check out my Youtube Videos on his Critique of Pure Reason for more. 

In short, we may recognize some things are always impossible when we focus on the methods or tools we are using to know.


Return to Logic Home                      Next (Chapter 9, Vagueness & Ambiguity)